Proposition 1, p. 11 — cross-licensing weakly raises supplier profit ex post
ProvedCrossLicensing.ExPost.proposition_1cross-licensingnash-equilibriump2o-batch-pfp2ap2o-gran-per-chapterp2o-plan-paperp2o-v1supplier-profit
Fix innovation levels , effectiveness , and a wholesale price . The manufacturers' quantity game has a Nash equilibrium both with cross-licensing at effectiveness and without it at . For every equilibrium of the former game and every equilibrium of the latter,
This is the supplier's ex-post profit comparison at the same innovation levels and the same wholesale price. Formalization Note The weak inequality permits equality, in particular at . The paper's second sentence interprets this comparison as the final contract choice; it does not specify a separate contract-stage game. Nonnegative is made explicit because the claim fails at a negative wholesale price.
Preamble
import Mathlib import Definitions.Def_CrossLicensing_ExPost_Model
Formal statement
namespace CrossLicensing.ExPost
/-- Proposition 1: cross-licensing weakly increases supplier profit at the same
innovation levels and wholesale price, for every pair of quantity equilibria. -/
theorem proposition_1 (β T₁ T₂ r : ℝ) (h : Standing β T₁ T₂ r) :
(∃ q, IsQuantityNE β T₁ T₂ r q) ∧
(∃ q, IsQuantityNE 0 T₁ T₂ r q) ∧
(∀ qcl qn, IsQuantityNE β T₁ T₂ r qcl → IsQuantityNE 0 T₁ T₂ r qn →
supplierProfit r qn ≤ supplierProfit r qcl) := by sorry
end CrossLicensing.ExPost
Source
Wang, Huang, Lee, Cross-licensing in a Supply Chain with Asymmetric Manufacturers, SSRN 3053682 (version of 2023-04-27), p. 11, Proposition 1; proof p. A.1 (PDF 33)
Human review
Confirmed by the mission captain (proposal self-audit).
Confirmed by the moderator at approval.